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Dosent spec. the geometry , I wont even guess with out the specs.
 

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Well....

gamma ramp said:
I want to get this frame

what size should I get for a rider that is 5'10 with a 29 inch inseam?

http://www.performancebike.com/weba...Id=10052&cm_re=Homepage-_-DOD-_-MTBFrame_Perf

The answer is here: http://www.performancebike.com/weba...es/performance/productinfo/30-1685-SIZING.gif

This is exactly why I suggest that people who aren't familiar with bike geometries and their body measurements should ride a bike before they buy it.

Performance gave you all the information you could ever need to determine if the bike is right for you and what size you should order. You only gave us your inseam measurement. In order to accurately determine the correct size, we'd need specific joint measurements (hip to knee, knee to bottom of the foot, shoulder to elbow, etc. etc. etc.). Proper fit is far more complex than "I'm this tall and I have x inseam".

With all that said, 5' 10" will likely put you in a 17"-19" frame, depending on the mfg.
 

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Really?

wildkyle90 said:
that looks like a road frame more than a mountain frame, i wouldnt get that
It doesn't look anything like a road frame to me. What makes you say that?
 

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Discussion Starter #6 (Edited)
actually, what attracted me to this frame was the fact that it did not
look like a mountain bike frame.

I have most of the components laying around to make it happen but the build will
not be for me so I can only estimate the size of the rider to a limited degree
here. I am going to give the bike to a guy I know who really can't afford one
right now.

I did see the sizing chart they have but the geometry of that frame
is so unusual for a mountain frame that I thought I would come here and
get other opinions about it

I was thinking that since the geometry more closely resembles a road
frame that it might be better to get a size smaller rather than get a frame
that was too big.
 

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if i had to make a guess on this one, id say your sitting right between a medium and large frame. but keninkc makes a great point how you really will never known until you actually get on the bike on ride it. Considering its only a 70 dollar frame, you wont be out too much coin if you make the wrong choice.

also it might depend on what kind of riding you/he is gonna be doing...maybe if your doing more all mountain id go with the medium, if your aiming more towards xc then a large..
 

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I think Ken in KC is overstating the complication of sizing a bike frame. You only touch it at three points - the handlebars, saddle and pedals. The handlebars can't be moved all that much - spacer stacks have a limited acceptable range of sizes on most frames, and stems come in a limited number of lengths, some of which make for strange handling.

The position of the crank is fixed and the position of the saddle is very malleable, especially its height. So as long as you've got a little standover clearance, I think that seat tube length is not that relevant (unless it would require you to get a longer-than-standard post to make it fit. Probably not a problem on a frame with such a flat top tube.)

My point being that you need the handlebars to be able to go in the right place relative to the crank. When I'm sizing my bikes, I'm a fan of the "magic number" - the length of the top tube. If you're happy with your current bike and its current stem size, measure the effective top tube and choose the frame size that most closely matches. If the head tubes are wildly different lengths and you won't be able to get your bar height right with some combination of stem size and angle, spacer stack, and flat vs. riser vs. inverted riser bar type choice, you're in a spot. But I'd be surprised if you have that problem.
 

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Read for context...

AndrwSwitch said:
I think Ken in KC is overstating the complication of sizing a bike frame. You only touch it at three points - the handlebars, saddle and pedals. The handlebars can't be moved all that much - spacer stacks have a limited acceptable range of sizes on most frames, and stems come in a limited number of lengths, some of which make for strange handling.

The position of the crank is fixed and the position of the saddle is very malleable, especially its height. So as long as you've got a little standover clearance, I think that seat tube length is not that relevant (unless it would require you to get a longer-than-standard post to make it fit. Probably not a problem on a frame with such a flat top tube.)

My point being that you need the handlebars to be able to go in the right place relative to the crank. When I'm sizing my bikes, I'm a fan of the "magic number" - the length of the top tube. If you're happy with your current bike and its current stem size, measure the effective top tube and choose the frame size that most closely matches. If the head tubes are wildly different lengths and you won't be able to get your bar height right with some combination of stem size and angle, spacer stack, and flat vs. riser vs. inverted riser bar type choice, you're in a spot. But I'd be surprised if you have that problem.

Perhaps you should reread what I said? If it's easy, given the information that's been provided, why didn't you answer the question?

What frame size, given 5' 10" and a 29" inseam?
 

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Ken in KC said:
Perhaps you should reread what I said? If it's easy, given the information that's been provided, why didn't you answer the question?

What frame size, given 5' 10" and a 29" inseam?
I don't think that all the measurements in the world will give a correct frame size. If I'm riding a road bike hard, I'm comfortable in a much lower position, with a longer reach than I am if I'm riding at a low power output. My measurements haven't changed. My road bike, however, has developed a longer reach over the period I've owned it - I used to ride it with bars and saddle level, now they're considerably lower and while the stem's a touch shorter, the bar angle puts the hoods further away.

To me, frame size depends on torso length, (EDIT: also arm length, with an appropriate bend in the elbow) the rider's flexibility and core strength, their power output, and their weight. That's why I believe in a "magic number" found through test-riding. I suppose if one could quantify flexibility and core strength, measure the rider's weight and weight distribution from the hip up only, and model all of that, that set of equations might be an okay predictive model for sizing frames.
 

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What the hell... OP, probably none of those sizes fit your friend. I'm 5'8" with a 31.5" inseam - so a much shorter torso than your friend. I ride a bike with a 590mm effective top tube and a 90mm stem. Their XL has a 584mm ETT, so unless your friend has a very upright position, he'll need a very long stem to make the reach comfortable. Their small would fit me well as a road bike, though. :)
 

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AndrwSwitch said:
What the hell... OP, probably none of those sizes fit your friend. I'm 5'8" with a 31.5" inseam - so a much shorter torso than your friend. I ride a bike with a 590mm effective top tube and a 90mm stem. Their XL has a 584mm ETT, so unless your friend has a very upright position, he'll need a very long stem to make the reach comfortable. Their small would fit me well as a road bike, though. :)
Exactly what I was going to say. If those specs on their site are correct, that bike has an extremely short ETT. I generally expect an 18" (Med) frame to have an ETT around 590-600. I would have someone at Performance see if they can confirm those specs.
 

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Ummm...

AndrwSwitch said:
I don't think that all the measurements in the world will give a correct frame size. If I'm riding a road bike hard, I'm comfortable in a much lower position, with a longer reach than I am if I'm riding at a low power output. My measurements haven't changed. My road bike, however, has developed a longer reach over the period I've owned it - I used to ride it with bars and saddle level, now they're considerably lower and while the stem's a touch shorter, the bar angle puts the hoods further away.

To me, frame size depends on torso length, (EDIT: also arm length, with an appropriate bend in the elbow) the rider's flexibility and core strength, their power output, and their weight. That's why I believe in a "magic number" found through test-riding. I suppose if one could quantify flexibility and core strength, measure the rider's weight and weight distribution from the hip up only, and model all of that, that set of equations might be an okay predictive model for sizing frames.

So this is fairly simple and I'm making it seems harder than it really is? Okay.
 

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Well yeah. I have a bike I like. If I want to know my magic number, I just measure the effective top tube and call it good. :)

My mountain bike has a 590mm top tube. I like my body position but feel like I'm just a touch further over my front wheel than I'd like and might be happier with a shorter stem (if it didn't screw up my position.) So I'd say my "magic number" is about 600mm, but I think I could be happy on anything in a 580-610mm range. I like my balls and find being able to dab or straddle the bike convenient, so I need my bike to have a standover height of 31.5" or less.

I'm only looking at two measurements - effective top tube length and standover. Or on the person, preferred reach and inseam length.
 
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